Keyboard



FIG. 1 is a front perspective view of a keyboard;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a right elevation view thereof;

FIG. 4 is a left elevation view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof.

The broken lines shown in the drawings of the keyboard are for the purpose of illustrating portions of the article and form no part of the claimed design. 

We claim the ornamental design for a keyboard, as shown and described. 